#include <REGX52.H>
#include <INTRINS.h>
sbit LED=P2^0;

void Delay(unsigned int t){
	while(t--);
}

void main()
{
		unsigned char Time,i;
		while(1)
		{
			for(Time=0;Time<100;Time++){
			  for(i=0;i<20;i++){
					LED=0;
			    Delay(Time);
			    LED=1;
			    Delay(100-Time);
				}
		  }
			for(Time=100;Time>0;Time--){
			  for(i=0;i<20;i++){
					LED=0;
			    Delay(Time);
			    LED=1;
			    Delay(100-Time);
				}
		  }
	  } 

}